HDMI is a completely digital format. It is also encrypted (in most cases including HD DVD and Blu-ray player output) so the signal must be decrypted by the receiving device before it can be displayed.
If you are seeing and hearing anything at all, your cable is working. If it completely fails or fails intermittently in a very obvious way, then you have a problem.
Unlike analog cables, there is really no way that HDMI can work to some degree without being essentially perfect.
Use whichever cable on either device as long as they both work.